upstream runc patch to avoid mqueue warning

[bcressey]

In #935 we added a patch to runc to avoid a warning when mounting /dev/mqueue. This should be suitable for upstream as-is, since the error happens on any Linux distro with SELinux enabled.

The warning can be seen more directly by attempting to mount mqueue on the command line:

$ mount -t mqueue mqueue /tmp/mqueue -ocontext=system_u:system_r:system_t:s0
mount: /tmp/mqueue: wrong fs type, bad option, bad superblock on mqueue, missing codepage or helper program, or other error.

# dmesg | tail -n1
[82324.512220] SELinux: mount invalid.  Same superblock, different security settings for (dev mqueue, type mqueue)

Adding any context option will trigger the warning and the mount failure; it's simply not supported by the kernel for the reason stated in the warning.

[bcressey]

Fixed upstream in opencontainers/runc#2558.